Datsun 521 IGN light on

[Datsun69]

So I have this Datsun 521 one and I have the ign light on

Thought it was my alternator so I replaced it with a new one I got a new battery to and the light it's still on

[datzenmike]

Throwing parts at it can get expensive and often the new parts are much poorer quality that the ones on it. Because of this a new part may not be working right out of the box and add a unknown problem that wasn't there before. Any chance you kept the old alternator? It may be a good spare.

 

 

I guess the only thing left is to change the voltage regulator.  I hate to say this as it's much better to solve the problem that eliminate it by swapping parts. So has the truck ever run right with the light off???

 

 

 

 

A volt meter across the battery terminals when running is a good check. Usually just over 14 volts when revved up slightly and about 12.5 with engine off.

While running, very briefly remove one of the battery cables. If the engine continues to run, the alternator is charging on it's own. If it stalls, then it was running on the battery.

[banzai510(hainz)]

did you forget to plug the T connector back in the alternator?